1. Field of the Invention
The present invention relates to a vacuum cleaner, and more particularly, to a dust collecting unit for a vacuum cleaner.
2. Background of the Related Art
FIG. 1 is a rear perspective view of an upright vacuum cleaner according to the related art. The upright vacuum cleaner includes a head 10 that moves across a floor surface, a body 20 which houses a device that generates a suction force which is transmitted through the head 10 so as to suck air containing foreign objects in through the head 10 as it moves across the floor, and a handle 30 installed on top of the body 20 which allows a user to direct the vacuum cleaner as necessary.
The head 10 moves in close proximity to the surface of the floor, and air is suctioned through a suctioning port (not shown) disposed on the bottom of the head 10. That is, the suctioning port (not shown) provides a main suctioning passage disposed at the bottom of the head 10 for suctioning outside air and guiding the intake of air.
A cylindrical dust collecting unit (not shown) is detachably coupled to the body 20. The dust collecting unit filters foreign objects from the air suctioned through the head 10.
FIG. 2 is a perspective view of a damper assembly provided inside the body 20 of the related art vacuum cleaner shown in FIG. 1. A fan motor (M) which generates a suction force when a current is applied thereto is housed inside the body 20. The suction force generated by the fan motor (M) allows air and foreign objects to be suctioned through the head 10 from the outside.
A body intake port 70 positioned above the fan motor (M) is also provided in the body 20. The body intake port 70 is in communication with one end of the dust collecting unit to guide air filtered inside the dust collecting unit inside the body 20. A passage 72 extends between the body intake port 70 and the fan motor (M) to guide air that is filtered by the dust collecting unit from the body intake port 70 to the fan motor (M. The passage 72 forms an interior space which communicates with the body intake port 70 and the fan motor (M) when the body 20 is assembled.
A damper assembly 80 is installed in the lower surface of the passage 72. The damper assembly 80 can be selectively opened to provide for communication between the inside of the body 20 and the outside to prevent overload of the fan motor. When a large quantity of foreign objects are amassed inside the dust collecting unit (not shown), the fan motor (M) experiences a great deal of difficulty in generating an adequate suction force, imposing an overload on the fan motor (M). To alleviate this condition, the damper assembly 80 is opened , providing for communication between the inside of the body 20 and the outside, and allowing the fan motor (M) to more easily suction air.
However, this structure has numerous problems. Specifically, the damper assembly 80, which is used to facilitate the suctioning of air by the fan motor (M) and prevent damage to the fan motor (M) is installed inside the body 20. Thus, a reaction time when an excessive amount of foreign objects are collected in the dust collecting unit is slow, limited by its installation internal to the body 20, and relies on user intervention.
Further, because there is no external indicator of the increased internal pressure, a user must notice a loss of suction to determine that the amount of foreign objects collected in the dust collecting unit is excessive and pressure has increased inside the body 20. The pressure increase is conveyed through the body intake port 70 and the passage 72 prior to taking action, thus further increasing the duration of an overload condition imposed on the motor (M). This extended duration overload condition which exists before the user becomes aware of the overload condition and takes action can cause the fan motor (M) to overheat and be damaged, resulting in unanticipated repair costs, loss of use, and other inconveniences which cause customer dissatisfaction.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.